<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <!-- 规定：块级元素-换行、行级元素-不换行 -->
    <h1>标题1</h1>
    <h1>标题1</h1>

    <span>普通文本1</span>
    <span>普通文本1</span>

    <p>夏日炎炎</p>
    <p>有你超甜</p>

</body>
</html>